1. Field
Exemplary embodiments of the invention relate to thin film transistor substrate and a method of manufacturing the thin film transistor. More particularly, exemplary embodiments of the invention relate to a thin film transistor substrate including an oxide semiconductor, and a method of manufacturing the thin film transistor.
2. Description of the Related Art
A thin film transistor is used for various electronic devices such as a flat panel display. The thin film transistor is used as a switching device or a driving element in the flat panel display including a liquid crystal display, an organic light emitting diode display, an electrophoretic display or the like, for example.
The thin film transistor includes a gate electrode, a source electrode, a drain electrode and a channel layer providing a channel between the source electrode and the drain electrode. The channel layer includes a semiconductor layer including amorphous silicon, polycrystalline silicon, oxide semiconductor or the like.
Amorphous silicon has a relatively low electron mobility, which may be about 1 square centimeters per volt second (cm2/V·s) to about 10 cm2/V·s so that a thin film transistor including amorphous silicon has relatively low driving characteristics. In contrast, polycrystalline silicon has a relatively high electron mobility, which may be about 10 cm2/V·s to about hundreds cm2/V·s. However, a crystallization process is added for forming polycrystalline silicon. Thus, it is difficult to form a uniform polycrystalline silicon layer on a large-sized substrate and manufacturing costs are high.
Oxide semiconductor may be formed by a low-temperature process, and may be formed easily large-scaled, and has high electron mobility. Thus, the thin film transistor including the oxide semiconductor has been being researched and developed actively.